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Biomedical subjects

J C Melchior

Publications and source records attributed to J C Melchior.

At least 37 records · Page 2Linked to original sources
PubMed1998

From malnutrition to refeeding during anorexia nervosa.

Anorexia nervosa is one of the most common forms of malnutrition observed in Western society in individuals without physical diseases, with an average risk of mortality of 20% in a younger population aged between 15 and 25 years. It is characterised by an initial dramatic decrease in food intake that leads to profound depletion in muscle and fat mass. During the course of the disease, the resting energy expenditure decreases proportionally to the loss of lean body mass with a decrease in thyroid hormone secretion. The metabolic adaptation during anorexia nervosa is similar to that observed during starvation with a relative sparing of protein stores. After an initial weight loss, the total energy expenditure is similar to that in normal individuals, with a decrease in resting energy expenditure and an increased energy-related physical activity. At the end stage of wasting, however, physical activity dramatically decreases as well as energy intake. This metabolic adaptation of semi-starvation is impaired during refeeding with an increase in the thermic effect of food and a high risk of refeeding syndrome with severe hypophosphatemia.

Anorexia Nervosa↗
PubMed1997

Serum cortisol and DHEA concentrations during HIV infection.

The progression of HIV infection is accompanied by severe immunodepression and cachexia, particularly during advanced stages. The immune depression is due largely to a dramatic drop in the number of CD4 cells. The loss of body weight is mainly due to a reduced fat-free mass with no change in adipose tissue. We determined the serum concentrations of cortisol and DHEA and their correlations with absolute CD4 cell counts and changes in body weight of HIV-positive men. The results of five retrospective and prospective studies indicate that the serum concentrations of cortisol and DHEA in HIV-infected patients were different from those of HIV-negative controls. Serum cortisol was elevated at all stages of infection (+20 to +50%, p < .05 to p < .001) particularly in AIDS patients (stage IV C). In contrast, the serum DHEA concentrations were closely correlated with the stage of HIV-infection, being higher in the early stages (stages II and III or > 500 CD4) than in advanced stages (IV C or < 500 CD4)-in the latter being below those of HIV-negative men-or in controls (+40 to 100%, p < .01 to p < .001). There was a negative linear correlation between the CD4 cell counts and cortisol (r = -0.4, p < .02) and a positive linear correlation with DHEA (r = +0.36, p < .01). There was no significant correlation between delta body weight and serum cortisol. In contrast, there was a negative correlation between serum DHEA and delta body weight (%) (r = -0.69, p < .0001) and a positive correlation with the cortisol/DHEA ratio (r = +0.61, p < .0001). There is thus a link between the circulating concentrations of adrenal steroids and the progression of immunosuppression and cachexia during HIV-infection. This raises the question of whether there is a cause-and-effect relationship between clinical progression and circulating steroid concentrations. Further investigations into the relationship between the ratio cortisol/DHEA and the immune response and cachexia should indicate the contributions of these steroids to the etiology of HIV infection and lead to the development of new therapeutic strategies.

Adult↗
PubMed1997

Metabolic aspects of HIV: associated wasting.

Despite recent progress in the treatment of human immunodeficiency virus (HIV) infection, wasting syndrome (WS) is now one of the major aspects of acquired immunodeficiency syndrome (AIDS). Malnutrition in HIV infected patients is characterised by a predominant loss of body cell mass (BCM), the amount of functional protoplasm in non-adipose tissue. This loss of BCM is correlated with a higher risk of AIDS events and a greater risk of mortality. If anorexia plays a major role in the development of the WS, some abnormalities in the metabolism drive the predominant loss of BCM. In the stable state, the resting energy expenditure (REE) is increased by about 10%. The REE is significantly correlated with the whole body protein turn over as measured by C13 leucine. This particular and only metabolic situation is associated with an increased insulin sensitivity and a high level in de novo hepatic lipogenesis. During periods of secondary infections, patients had a striking average weight loss, resulting from the combination of anorexia and dramatic elevated REE.

Basal Metabolism↗
PubMed1997

Nutritional status of HIV-seropositive subjects in an AIDS clinic in Paris.

OBJECTIVE: To measure the prevalence and analyse the characteristics of malnutrition among subjects attending an AIDS outpatient clinic and a day care center, to improve the nutritional management of HIV-infected subjects. DESIGN: Prospective cross-sectional study. SETTING: AIDS clinic in a University Hospital in Paris. SUBJECTS: 124 HIV-seropositive adults attending the clinic. MAIN OUTCOME MEASURES: Evaluation of nutritional status using anthropometry, impedancemetry, plasma albumin and pre-albumin assays. Degree of malnutrition, defined by the percentage of body weight loss (BWL), calculated by reference to the usual body weight. RESULTS: Among the 124 subjects recruited (M:F sex ratio: 3.3, mean age: 36.3 +/- 7.2 y), 77 (62.1%, 95%CI: 53.9-70.3) had normal nutrition status (BWL < or = 5%), 16 (12.9%, 95%CI: 7.0-18.2) moderate malnutrition (5% < BWL < or = 10%), 21 (16.9% 95%CI: 10.3-23.5) intermediate malnutrition (10% < BWL < or = 20%), and 10 (8.1%, 95%CI: 3.3-12.9) severe malnutrition (BWL > 20%). BWL was related to the CDC class (variance analysis, P < 9 x 10(-5)) and CD4 cell count (P < 3 x 10(-5)). Malnutrition was observed even among CDC class A subjects (14.9%). BWL was also related to the body mass index (P < 3 x 10(-6)), lean body mass (P < 3 x 10(-5)), body fat (P < 7 x 10(-6)), and as assessed by impedancemetry, body cell mass (P < 10(-5)) an the extra/intra cellular water ratio (P < 2 x 10(-4)). The decrease in lean body mass was related to the decrease in body cell mass. CONCLUSIONS: Given its high frequency, malnutrition should be prevented, detected, monitored and treated from the early stages of HIV infection among patients attending AIDS clinics in order to improve survival and quality of life.

Acquired Immunodeficiency Syndrome↗
PubMed1996

High resting energy expenditure in normal-weight bulimics and its normalization with control of eating behaviour.

Resting energy expenditure (REE) has been found to be lower in normal weight-bulimics (NWBs) than in controls and it was speculated that metabolic abnormalities might underlie bulimia. This study consisted of a longitudinal assessment of REE, body composition and energy intake before, during and after the control of eating behaviour, with comparisons between REEs in NWBs, those in controls, and estimated basal energy expenditure (EBEE). NWBs in acute phase of bulimia were assessed the 1st, 2nd, and last day of a one-week hospitalization that warranted compliance with normal diet. Assessments were then repeated after a six-week outpatient psychotherapy. Mean REE in NWBs was higher than that in controls and EBEE on admission. It decreased down to normal rate at discharge and at therapy termination. Fat-free mass (FFM) decreases slightly during hospitalization despite a weight-maintenance diet, but REE-FFM ratio also decreased significantly. Metabolic factors which might account for these results are discussed. Data suggest that: (1) caloric requirements in NWBs were higher than estimated weight-maintenance rations; (2) binge-eating increased REE; (3) control of eating behaviour decreased REE.

Adult↗
PubMed1996

Efficacy of 2-month total parenteral nutrition in AIDS patients: a controlled randomized prospective trial. The French Multicenter Total Parenteral Nutrition Cooperative Group Study.

OBJECTIVE: To evaluate the efficacy of total parenteral nutrition in AIDS patients. DESIGN: A prospective, randomized, controlled, multicentre trial. METHODS: Over a period of 2 months, 31 malnourished and severely immunodepressed AIDS patients were assigned to receive either dietary counselling (n = 15) or home total parenteral nutrition (TPN; n = 16) via a central venous access after an educational program. Results were analysed by intent-to-treat basis. RESULTS: Bodyweight change was +8 kg (+13 +/- 3%) in the TPN group and -3 kg (-6 +/- 2%) in the control group (P < 0.0006). Lean body mass increased in the TPN group (+9 +/- 3%) and decreased in the control group (-5 +/- 3%; P < 0.004) while body cell mass increased in the former (+15 +/- 4%) and decreased in the latter (-12 +/- 6%; P < 0.002). Nutritional subjective global assessment, subjective self-reported health feeling and Karnofsky index were also improved by TPN. Infection line sepsis incidence remained low (0.26 per 100 patient-days). However, no difference in survival rate was exhibited between the two groups by the log-rank test. CONCLUSION: We conclude that home TPN is an efficient treatment of malnutrition in severely immunodepressed AIDS patients.

Acquired Immunodeficiency Syndrome↗
PubMed1996

Polymorphisms of uncoupling protein (UCP) and beta 3 adrenoreceptor genes in obese people submitted to a low calorie diet.

OBJECTIVE: To investigate whether the genetic polymorphisms of the uncoupling protein (UCP) and beta 3 adrenergic receptor (beta 3 AR) were associated with differences of weight loss in obese patients submitted to a low calorie diet. DESIGN: Longitudinal, clinical intervention study of a 25% restriction in energy intake with respect to genotypes. SUBJECTS: 163 patients with a body mass index above 27. MEASUREMENTS: Body weight and body mass index at baseline and after 2.5 months, genotypes by polymerase chain reaction followed by enzymatic digestion. RESULTS: For the UCP polymorphism, two alleles, 1 and 2 were identified with respective frequencies of 0.27 and 0.73. The allele 1 was associated with lower body weight loss after diet: 4,6,5.7 and 7.1 kg for the 1-1, 1-2 and 2-2 genotypes respectively (P < 0.05). No difference in weight loss was found according to the beta 3 AR Trp64Arg mutation. CONCLUSIONS: A genetic variant of the UCP gene is associated with a resistance to low calorie diet. This result, together with previous data on body weight gain, supports the hypothesis of a role of UCP and brown adipose tissue in the body weight regulation in humans. The importance of the Trp64Arg mutation of the beta 3 AR in the resistance to low calorie diet is still to demonstrate.

Adult↗
PubMed1995

Energy balance in children and young adults receiving haemodialysis for chronic renal failure.

This study was designed to determine the contribution of energy expenditure to the energy imbalance seen in uraemic children. Resting energy expenditure (REE) was measured using open-circuit indirect calorimetry in eight uraemic haemodialysed subjects aged 9.3-20.4 years and in 10 healthy children. Linear correlations between REE and both body weight and fat-free mass as measured by anthropometry were found in both controls and uraemic subjects (respectively: r = 0.76 and r = 0.88 for body weight and r = 0.73 and r = 0.90 for fat-free mass). Measured REE in uraemic patients was not different from the value predicted by using actual body weight and fat-free mass in the regression equation of REE on body weight and fat-free mass in controls (paired t test: p = 0.70 and p = 0.19 respectively). These data suggest that the energy imbalance seen in uraemic children is not due to increased energy expenditure and is therefore probably due to decreased food intake.

Journal Article↗
PubMed1995

[How to assess preoperative nutritional status?].

The assessment of nutritional status of patients should rely on sensitive and specific evaluation tools. However a universally recognized criterion of severity of denutrition is still lacking. The most important clinical indicator is the weight. The speed of weight loss is an important point to consider: a loss of 2% within one week is equivalent to 5% in one month and 10% in six months. Other anthropometric indices such as the triceps skin fold and the mid arm muscle circumference have not shown, when considered alone, to increase the risk carried by denutrition. Therefore other clinical indicators have to be considered, the association of which is suggestive of malnutrition, but none when considered alone is neither specific nor pathognomonic. Food intake is quantified by questioning. Among the biological markers representative of the pool of circulating visceral proteins is albumin. Numerous studies have demonstrated a morbidity and mortality increase when the plasmatic albumin concentration is less than 30 g.L-1. Other proteins with a shorter half-life, such as transferin, prealbumin and retinal binding protein have been recommended. The determination of muscular mass is also a tool for nutritional assessment. The muscular function and immunologic tests such as the lymphocyte count and cutaneous reactivity to various antigens have been assessed as denutrition indices. The determination of body mass composition by bioelectrical impedance could become the technique of choice for nutritional assessment. However its use for peri-operative evaluation has not been validated prospectively. Because of the lack of reliability of markers when considered alone, several authors produced multivariate nutritional indices.(ABSTRACT TRUNCATED AT 250 WORDS)

Humans↗
PubMed1994

Palatability of a meal influences release of beta-endorphin, and of potential regulators of food intake in healthy human subjects.

The effect of the palatability of a meal was tested on the post-prandial release of several gut hormones or neuropeptides which are known to have an effect on intake and satiety. Hormonal response was determined in plasma during the 3 h after a highly palatable and energy-rich meal or after the same meal served cold in a poorly acceptable form, as well as while fasting. The early post-prandial pancreatic polypeptide and neurotensin response was significantly higher after the highly palatable meal than after the cold one. Later responses differed only for pancreatic polypeptide. No difference was observed in cholecystokinin and neuropeptide Y levels. Post-prandial levels of beta-endorphin were elevated only after the cold meal and were associated with an elevated response of ACTH. We suggest that beta-endorphin might be secreted in response to an aversion towards the non-palatable cold meal. This could, subsequently, inhibit the cephalic phase of pancreatic polypeptide response and the early post-prandial response of neurotensin by a central anticholinergic effect. This study evidences an effect of palatability on the modulation of the digestive hormonal response after a meal.

Adult↗
PubMed1994

Mechanisms of decreased food intake during weight loss in adult Crohn's disease patients without obvious malabsorption.

Because weight loss is common in colonic Crohn's disease and is poorly correlated with disease activity, we analyzed food intake in 63 patients without malabsorption, 30 patients with weight loss (9.2 +/- 4.2 kg), and 33 patients without weight loss. Energy and protein intakes were lower in patients with weight loss than in those with stable weight (P < 0.01). In the former group, food restrictions were more numerous (P < 0.01) and visual analog scales showed less hunger, decreased appetite, and fewer sensations of pleasure related to eating, as compared with the other group (P < 0.01). Food intake reduction was also related to depressive mood and medical advice. However, there was no difference between groups in fecal energy wasting and resting energy expenditure. Weight loss in Crohn's disease may be due to a decrease in food intake rather than to an increase in energy cost of the disease. Thus, focus of attention on the diet is crucial to prevent malnutrition.

Adult↗
PubMed1994

Diaphragmatic function in severely malnourished patients with anorexia nervosa. Effects of renutrition.

The effects of malnutrition and refeeding on nutritional indices, pulmonary function, and diaphragmatic contractile properties were studied in severely malnourished patients with anorexia nervosa. Fifteen patients were evaluated upon hospital admission (Day 0) and on Days 7, 30, and 45 after starting feeding. Spirometry, lung volumes, and arterial blood gases were measured at each time interval, as were contractile properties of the diaphragm as assessed by transdiaphragmatic pressure generated during electrical phrenic nerve stimulation (Pdistim) and a maximal sniff maneuver (Pdisniff). Anthropomorphic and biochemical measurements were performed at each time interval. Patients were severely malnourished upon admission; mean body weight was 37.1 +/- 4.7 kg (63% ideal body weight). During nutritional support, body weight increased significantly to 42.9 +/- 4.6 kg on Day 45 (p < 0.01), as did muscle mass: 11.2 +/- 4.1 kg on Day 0, to 16.6 +/- 4.9 kg on Day 45 (p < 0.01). Vital capacity and FEV1 increased significantly by Day 30 (p < 0.05). Lung volumes were unchanged. Mean arterial blood gas values were also within the normal range at Day 0; PaO2, 92.6 +/- 2.4 mm Hg and PacO2, 41.0 +/- 1.5 mm Hg. Four patients, however, had an increased PacO2 (> 42 mm Hg) at Day 0, which returned to normal by Day 30. Diaphragmatic contractility was severely depressed initially; Pdistim, 15.9 +/- 1.4 cm H2O; Pdisniff, 65.4 +/- 5 cm H2O; but it significantly increased with nutritional support by Day 30 to 22.5 +/- 1.9 and 84.6 +/- 4.7 cm H2O, respectively. We conclude that diaphragmatic function is severely impaired in malnuorished patients free of other coexisting

Acute Disease↗
PubMed1993

Resting energy expenditure in human immunodeficiency virus-infected patients: comparison between patients with and without secondary infections.

Resting energy expenditure (REE) was measured in 165 malnourished patients with human immunodeficiency virus infection and compared with that of 31 control subjects. Of these patients, 129 had no symptoms of secondary infections (NI), whereas 36 had evolving secondary infection (I) despite a body temperature < 38 degrees C. Mean REE was 11% higher in the NI group than in the control group (P < 0.05); it was 34% higher in the I group than in the control group (P < 0.001) and 21% higher than in the NI group (P < 0.01). In all cases the best predictive variable for REE was the fat-free mass (FFM) (r = 0.77, P < 0.001 in NI; r = 0.70, P < 0.001 in I; r = 0.78 in the control group. The REE-FFM ratio was 152.5 +/- 1.2 and 207 +/- 5.4 kJ.kg-1.d-1 in the NI and I groups, respectively. A high energy expenditure may be a harbinger of secondary infection in acquired immunodeficiency syndrome and may participate in accelerated weight loss.

AIDS-Related Opportunistic Infections↗